btrfs: fix inconsonant inode information

When iputting the inode, We may leave the delayed nodes if they have some
delayed items that have not been dealt with. So when the inode is read again,
we must look up the relative delayed node, and use the information in it to
initialize the inode. Or we will get inconsonant inode information, it may
cause that the same directory index number is allocated again, and hit the
following oops:

[ 5447.554187] err add delayed dir index item(name: pglog_0.965_0) into the
insertion tree of the delayed node(root id: 262, inode id: 258, errno: -17)
[ 5447.569766] ------------[ cut here ]------------
[ 5447.575361] kernel BUG at fs/btrfs/delayed-inode.c:1301!
[SNIP]
[ 5447.790721] Call Trace:
[ 5447.793191]  [<ffffffffa0641c4e>] btrfs_insert_dir_item+0x189/0x1bb [btrfs]
[ 5447.800156]  [<ffffffffa0651a45>] btrfs_add_link+0x12b/0x191 [btrfs]
[ 5447.806517]  [<ffffffffa0651adc>] btrfs_add_nondir+0x31/0x58 [btrfs]
[ 5447.812876]  [<ffffffffa0651d6a>] btrfs_create+0xf9/0x197 [btrfs]
[ 5447.818961]  [<ffffffff8111f840>] vfs_create+0x72/0x92
[ 5447.824090]  [<ffffffff8111fa8c>] do_last+0x22c/0x40b
[ 5447.829133]  [<ffffffff8112076a>] path_openat+0xc0/0x2ef
[ 5447.834438]  [<ffffffff810c58e2>] ? __perf_event_task_sched_out+0x24/0x44
[ 5447.841216]  [<ffffffff8103ecdd>] ? perf_event_task_sched_out+0x59/0x67
[ 5447.847846]  [<ffffffff81121a79>] do_filp_open+0x3d/0x87
[ 5447.853156]  [<ffffffff811e126c>] ? strncpy_from_user+0x43/0x4d
[ 5447.859072]  [<ffffffff8111f1f5>] ? getname_flags+0x2e/0x80
[ 5447.864636]  [<ffffffff8111f179>] ? do_getname+0x14b/0x173
[ 5447.870112]  [<ffffffff8111f1b7>] ? audit_getname+0x16/0x26
[ 5447.875682]  [<ffffffff8112b1ab>] ? spin_lock+0xe/0x10
[ 5447.880882]  [<ffffffff81112d39>] do_sys_open+0x69/0xae
[ 5447.886153]  [<ffffffff81112db1>] sys_open+0x20/0x22
[ 5447.891114]  [<ffffffff813b9aab>] system_call_fastpath+0x16/0x1b

Fix it by reusing the old delayed node.

Reported-by: Jim Schutt <jaschut@sandia.gov>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Tested-by: Jim Schutt <jaschut@sandia.gov>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 87f1e0cf26f8..447612d3a16a 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2509,6 +2509,11 @@ static void btrfs_read_locked_inode(struct inode *inode)
         int maybe_acls;
         u32 rdev;
         int ret;
+        bool filled = false;
+
+        ret = btrfs_fill_inode(inode, &rdev);
+        if (!ret)
+                filled = true;
 
         path = btrfs_alloc_path();
         BUG_ON(!path);
@@ -2520,6 +2525,10 @@ static void btrfs_read_locked_inode(struct inode *inode)
                 goto make_bad;
 
         leaf = path->nodes[0];
+
+        if (filled)
+                goto cache_acl;
+
         inode_item = btrfs_item_ptr(leaf, path->slots[0],
                                     struct btrfs_inode_item);
         if (!leaf->map_token)
@@ -2556,7 +2565,7 @@ static void btrfs_read_locked_inode(struct inode *inode)
 
         BTRFS_I(inode)->index_cnt = (u64)-1;
         BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
-
+cache_acl:
         /*
          * try to precache a NULL acl entry for files that don't have
          * any xattrs or acls
@@ -2572,7 +2581,6 @@ static void btrfs_read_locked_inode(struct inode *inode)
         }
 
         btrfs_free_path(path);
-        inode_item = NULL;
 
         switch (inode->i_mode & S_IFMT) {
         case S_IFREG: